I essentially used a sprite billboard, like the trees in mario 64. Blockbench doesnt inherently support that but you can sorta fake it if you apply code in the rotation values during an animation. Assign your texture to an upright plane, then in your animation add rotation keyframe, but instead of an x,y,z value, plugin like this:

X=query.camera_rotation(0)
Y=query.camera_rotation(1)
Z=0

It should force the plane to face the camera no matter how you rotate the view. It has some limitation, if you also normally rotate the plane then the billboarding breaks, but can be useful for some models, like for instance its how I made the space helmet bubble for my orbit woman model.